Perhaps one less lonely question in the world tonight

I hope that it is not silly if I would ask the Lichess community a question. How does lichess find out if a player uses a computer engine? I would really appreciate your answer. Thanks in advance!

The information you're asking about isn't for me to share.
In my opinion, almost all anti-cheat discussions should remain completely clandestine.


What you need to know about cheating at Lichess is:

1. Nobody has a more thorough and competent anti-cheat division than Lichess. Nobody even starts to begin to almost possibly kind of begin to start to almost compare to what Lichess does in order to identify and extirpate cheaters.


That's coming from someone that's been through 10 different chess sites since the 90s.


2. Anywhere else, including several well established paysites, does not employ the methods, attention, energy, and diligence in conquering this problem, than Lichess does. Again, not even close.


3. If you suspect someone of cheating, please report them by clicking on their name and then clicking on the 'hazard' symbol at the top right of their profile.

From there, simply select "cheating" as the reason for your report, copy-paste the link of your game, and very briefly state what stood out to you that makes you think that they might be cheating.


4. As a whole, cheating in online chess is at a very bare minimum. Many of the rewards for cheating that are present in other online video games, are not really present with chess.

There are dozens of obvious reasons for this, but the main one is that it must require a depressing amount of work and energy in order to look legitimate. They couldn't possibly look themselves in the mirror and not see the biggest loser on the planet staring back at them right before opening the medicine cabinet and reaching for the pills.

"If you would have told me, 10 years ago, that I'd be online faking as though I had intellect, I wouldn't have believed you. FML, even I can't stand the sight of myself anymore." - Chess Cheaters.

Our experience is that they will assume that Lichess has the weakest anti-cheat, try a few times, fail a few times, get sick of making new profiles, and then slink and slither off to other sites where cheating is much easier to get away with.


5. On top of cheating being almost a non-factor, Lichess deals with the issue as competently as possible.

Thanks to Lichess' ceaseless work over the years, in combination with the slackness of other sites that allow people to cheat, completely unabated, for years and years and years, where those subscription fees keep flowing in at the cost of the integrity of those sites, we have a situation where an evolution has taken place, where Lichess remains the BY FAR most cheat-free gaming site (approx. 2:100), while others suffer a cheating epidemic upwards of 15:100.


If cheat-free chess is what you're after, you're in the only appropriate place.

See you on 'The 64'!

Totally agree with everything Onyx Chess said apart from the 15:100 ratio.A site I won't name stopped archiving unrated games a while back,and the cheats immediately jumped in to use that to fine-tune their engine techniques.A ratio of 40+% is not an exaggeration.
The cheat has already admitted to himself that everyone else is better than he is.
This mantra may take the edge off the burning desire to hit the cheat with a brick for wasting your time.

I trust that Lichess does more to address the problem than other sites. But when I consider the problem (as well as other widespread social problems) it seems unlikely that cheating can ever be eliminated 100%.

Given the measures that are taken to eliminate cheating, I don't think it's possible for someone to use an engine to make all of their moves. They would quickly be caught and banned. I assume the cheating that persists on this site involves partial use of engines (amongst other things such as falsely inflating ratings, possible collusion with stronger players, etc.).

I think some people use opening books to start the game to avoid getting trapped or stuck playing the rest of the game from a bad position. Others use special software that integrates engines into gameplay and make use of the engine randomly throughout the game - including blitz and bullet games. That way, their blunder/inaccuracy/mistake count looks somewhat normal (due to their own bad moves) but their strength is still artificially enhanced by the engine. I also assume it is more difficult to catch these types of cheaters because their engine usage pattern is more randomized - however, there may still be statistical methods that Lichess uses to detect those patterns and/or other methods of detecting such software.

That said, it's still obviously possible for someone to make use of an engine that is separated from the computer used to play the game. Manually entering each move into a second computer is possible but that would limit cheating to games with longer time control. However, given the Lichess API, I suspect that it's possible to stream their live game to a second system that is linked to an engine. The cheater would then be able to reference the other system as they play the game without having to manually enter moves on the second machine or run suspect software on the machine they use to login to Lichess.

What amazes me is the time, knowledge and effort required to circumvent anti-cheat detection. If people spent half that time studying chess, they would be better players and have less "need" for such measures - but that's true of most crime and anti-social behavior. Even more disheartening is that there are likely people with almost no knowledge of chess who do these things simply for the challenge (like hackers who break into certain networks simply for the challenge of it). I'm sure they take pride in maintaining a high rating while proudly remaining ignorant of the nuances of chess.

Does that mean that online chess is a waste of time? I don't think so. But I do think that becoming a better player should take precedence over getting a higher rating. While it's possible for someone to manipulate or unfairly affect your rating in the short term by cheating, they can't stop you from improving - even if they use an engine against you. Over time, you will improve and your skills will be reflected in your rating and it will become more difficult for cheats to beat you without exposing themselves through excessive engine use. So aside from the efforts being made by Lichess to detect and ban cheating, I think the best thing we can all do to thwart cheating is to become better chess players.

The curiosity  came as I have observed a player during a 'rapid' tournament, he was crushing one game after the other, and I was like very impressed of his playing. Some days later, I watched him playing again, and he was not anymore playing that good. I checked out all his games and there was a kind of pattern like he was winning 11 games in a row and then lost two to three games; I just find it very weird. His rating was also over 2000, but he lost a few games against opponents with  ratings below 500! I know that this is hard to tell. I like studying players, it is like detective work.

Hmm,  I don't really care that much if some people need to use some computer engines to have their fun, I've had had oponents being flagged as cheaters but still took this as a challenge to end the game no matter if I have had not the least of chance to win it. I don't take it hard. For me a game is a game: even against a computer engine.

Like what I have already said, it is out of pure curiosity that I published the question. I wanted to finally find an answer to this matter - and because of your replies, I come to understanding that cheaters can be detected if being correctly investigated in the internet.

I would never report a cheater, for me that is nothing but a childish act. It is their problems if they have principles or none.

Friends, I would like to give special thanks for giving a lot of effort to answer my post. Thank you very much!

"ratings below 500"
I never saw something like this here on lichess. Is it even possible? Please show!

This thread made me wonder about the potential conflict between the open source nature of lichess and the need to hide anti-cheating methods from the general public.

Does lichess use a purely human element to its anti-cheating methods, code obfuscation or even non FOSS code for this ?

I don't think so, that would be too expensive for Lichess. To be able to detect all computer engines on the whole planet, you may as well hire the whole Pentagon.

You can't post in the forums yet. Play some games!